I've got the same issue I wish Canon would re-write the plugin and let you select paper type, feed, margins etc consistantly and all from the computer. I hope Canon reads these forums Marc
There is a "reason" for the different border sizes.
The cassette and manual feed paths are different, and mechanically the printer handles the paper differently, so the border sizes are different.
The manual feed path is also/mostly used for roll feed and for roll feed there is more paper outside the printed area to grip the paper.
There is a way to print 17x22 as long as the paper is thick/heavy enough. Select POP Board as the media and a 4th paper path is opened, feed from the front into a slot that is opened by th printer about an inch above the cassette.